There are various elevator and load transport systems which have a number of tension elements, for example flat or V-ribbed belts, for carrying and driving the elevator car or a platform. The tension elements are typically fixed in the region of a counterweight, carry a counterweight, are deflected at an upper (driving) pulley and then, for example in the form of an underloop, run through under the elevator car and are fixed on the other side of the elevator car. This fixing is also designated as a car-side tension element fixed point, whereas fixing in the region of the counterweight is designated as a counterweight-side tension element fixed point.
There are various possibilities for implementing these tension element fixed points in concrete terms.
In the elevator and load transport systems, during assembly, but also during maintenance, it is determined whether the tension elements of a suspension cord are uniformly loaded, for example in order to test whether uniform load distribution is ensured. The outlay hitherto involved in this respect is relatively high, and the equipment which is sometimes used is costly and sensitive.
A corresponding measuring instrument is known from the published patent application EP 573831 A1. This measuring instrument comprises a torsionally and flexurally resistant force sensor, so that as accurate evidence as possible as to the instantaneous tensile forces of a rope can be obtained. A tension element is retained at two points, and the tension element is deflected in the middle between these two points and is measured. When a load limit is overshot, for example, a signal may be triggered.
Another solution for tension element monitoring is known from the published patent application EP 1847501 A1. The means for tension element monitoring are fastened firmly to a guide track of an elevator system. The belt-like tension element to be monitored is led past a sensing surface. A sensing arrangement is integrated into this sensing surface, for example so that variations in the structure of the monitored tension element can be detected.
A type of measuring gage or alignment aid is known from the published patent application EP 0 498 051 A2. However, this measuring gage or alignment aid is not designed as a measuring gage for clamping between two tension elements, but serves instead for the alignment of guide rails.